Means for intercepting liquid refrigerant



Patented Oct. 9, 1951 MEANS Foa INTERCEPTING LIQUID REFRIGERANT James C.McBroom, Van Nuys, Calif., as'signor of one-half to Annandale Cuthill,Los Angeles,

Calif.

Application December 6, 1947, Serial No. 790,093

4 Claims. '(Cl. 62-115) This invention relates to means for thedisintegration, interception, and recirculation to the evaporator of arefrigerating system of such liquid that is in the form of globulescarried in the stream of vaporized refrigerant moving to. the compressorof said system.

, The compressor of a conventional refrigerating system receivesvaporized refrigerant, as, for instance, ammonia, compresses the sameand forces said refrigerant to a condenser where it is cooled andreturned as a liquid to an evaporator where heat exchange againvaporizes the refrigerant, whence it passes to an accumulator. Therefrigerant used is usually a powerful solvent that is capable ofdissolving oil. Since conventional compressors embody moving parts thatare oiled or otherwise lubricated, it is undesirable to pass liquidrefrigerant therethrough with a consequent removal of lubricant andresultant galling of the compressor mechanism. However, the refriger-vant when gasified, does not dissolve or otherwise attack the lubricant.In conventional systems, the vaporized refrigerant travels at highvelocities, and tends to carry with it globules of liquid refrigerant tothe compressor.

An object of the present invention, therefore, is to provide means, inan otherwise conventional refrigerating system, without adverselyrestricting the flow of refrigerant in the system, that insures that noliquid refrigerant entersthe compressor of the system.

Another object of the invention is to provide a refrigerant accumulator,in a refrigerating system, from which vaporized refrigerant is drawninto a compressor and to embody in said accumulator means that, withoutadversely restricting the flow of refrigerant in the system, will breakup or disintegrat such globules of liquid refrigerant that maydeleteriously affect said compressor.

Another object of the invention is to provide the means above indicatedthat will not only break up the globules but will also cause theresultant liquid to drain to the bottom of theaccumulator forrecirculation to the evaporator.

Another object of the invention is to provide the means above indicatedthat will break up the globules without adversely restricting the highvelocity flow of refrigerant in the system.

My invention also has for its objects to provide such means that arepositive in operation, convenient in use, easily installed in a workingposition, and easily disconnected therefrom, economical of manufacture,relatively simple, and of general superiority and serviceability.

The invention also comprises novel details of construction and novelcombinations and arrangements of parts, which will more fully appear inthe course of the following description. However, the drawings merelyshow and the following description merely describes one embodiment ofthe present invention, which is given by way of illustration or exampleonly.

In the drawings, like reference characters designate similar parts inthe several views.

Fig. l is a semi-schematic view of a typical refrigerating systemembodying the novel liquid disintegrating and intercepting accumulatormeans herein contemplated.

Fig. 2 is an enlarged longitudinal section view of said means.

The conventional system shown in Fig. 1 embodies a compressor 5 thatdischarges refrigerant through a pipe 6 to a cooled condensing tower 7.After a heat exchange operation in said unit, the liquid refrigerantpasses through pipe 8 into a liquid refrigerant reservoir 9. From saidreservoir 9, the liquid refrigerant is forced through the pipe I0 intothe interior of a pipe II, said pipe I0 projecting a short distancewithin the pipe II in a direction toward an accumulator I2. A downwardlydirected end I3 of pipe II discharges said refrigerant into theaccumulator. The liquid refrigerant is then forced through the pipe I4to an evaporator I5, where heat exchange, in the coils thereof, takesplace and the refrigerant is vaporized and returned to theaccumulator I2by the pipe II. 'The vaporized refrigerant in the accumulator I2 is thendrawn through the pipe I6 to the compressor 5.

The accumulator I2 comprises a closed elongated tank that is preferablyvertically arranged with its vapor outlet pipe I6 at the top, its inletpipe I I for mixed vapor and liquid refrigerant entering the tankintermediate its top and bottom, and said bottom serving to receive theliquid refrigerant discharged from the downwardly directed end I3- ofinlet pipe II. A liquid outlet pipe [4 conveys liquid refrigerant backto the evaporator I5. I

The refrigerant, vaporized in the evaporator I5, passes through pipe I Ito the accumulator I2. However, the pull of the compressor exerted onthe vapor, frequently draws relatively large globules or slugs ofmoisture into pipe ['6 with th deleterious effects above noted. Novelscreen means I'Iare placed in the path of such globules for the purposesof breaking them up and drain.- ing them back into the bottom of tankI2.

The accumulator I2 and the evaporator I5 are 3 disposed vertically inrelation one to the other in such a, fashion that the liquid level inthe accumulator l2 is always maintained below the end l3 of vapor andliquid inlet pipe II, and the liquid refrigerant in the evaporator fillssaid evaporator. to a level sufficient. to -maintain the most efiicientheat exchange. These liquid levels are maintained by an automatic liquidlevel control switch (not shown) which actuates a shutofi valve in pipeIt should the liquid level in accumulator 12 rise above the desiredlevel.

The means N, that is shown, comprises two sloped or angled screens l8and;l .9, one abovethe other and mounted in tank, 12.;between inlet pipeII and vapor outlet pipe 16. The screens l8 and I9 are placed at such anangle as to facilitate the flow of liquid, collected on the low'sides ofthe screens, and return said flow to the bottom of the tank l2. Suitablesupport lugs are provided on which said screens may rest or to whichthey may ,be secured by bolts or welds. The screens, in thisillustration, are of the typethat are known as No. 4 mesh, that is,spacing of wires. Thus, vapor is'free to pass through the screeninterstices, whereas globules encountering the screen wires aredisintegrated, flow down the slope of thescreen and fall back to thebottom of the tank. The screens are made of corrosion resistant wire andare advantageously made of stainless steel or tinned iron wire. Whilethe screens, as described, are of No. 4 mesh, which has proved to be ofoptimum size for the average commercial refrigerating systern,variations in the mesh size may be advisable for different systems. Theobject is to use a mesh size which is small enough to intercept theglobules but not too small to restrict the flow of vapor refrigerant inthe system.

While other forms of foraminous members may be used, it is preferable touse wire screen because liquid will 'flo'w along the wires or strandswithout interruption and theresult'a-nt accumulations of liquid whichmay clog the interstices. Thus, the screen openings are free 'to passvapors or, gases to the compressor.

Although I consider the installation of a vertical ftank I2 to bepreferable, itis possible to construct a satisfactory installationcontaining means I7 in an. horizontally disposed "tank.

While I have illustrated and described what Lnowv regard as thepreferred embodiment of my invention, the constructionis, of course,subject to modifications ,without departing from the spirit and scope ofmy invention. I, therefore, do -not .wish to restrict myself-to theparticular form of construction illustrated and described, but desire toavail myself of all modifications that may fall within the scope of theappended claims.

I-Iaving thusdescribed my invention, what I claim and desire to secureby Letters Patent is:

1. Ina refrigerating system having a compressor, a condenser, anevaporator and an accumulator, a reirigerant vapor flow connection fromthe upper end of the accumulatorto the compressor, a series fiowconnection between the former and the evaporator comprising aconnection, for how of liquid refrigerant from the bottom of theaccumulator tothe bottom of the evaporator and a connection for flowofvaporized refrigerant from the top of the evaporator to an intermediatepoint .of the accumulator, ,saidlatter.;connection extending into theinterior of the accumulator and being, downwardlydirected, a

abre st condenser and into said latter connection where- 4 by the sameconducts condensed refrigerant from the condenser in addition to thevaporized refrigerant from the evaporator into the accumulator to fallfrom the downwardly directed connection extension into the bottom of theaccumulator, and mesh screenmeans extending completely across theaccumulator between said downwardly directed extension and theconnection to the compressor for unrestrictedly passing refrigerantvapors to the compressor and for intained in said vapors.

- 2. In a refrigerating system having a compressor, acondenser, anevaporator and an accumulator, a refrigerant vapor flow connection fromthe upper end of the accumulator to the compressor, a series flowconnection between the former and the evaporator comprising a connectionfor flow of liquid refrigerant from the bottom -,of the accumulator to,the bottom of the evaporator; and a connection for flow of vaporizedrefrigerant fromjthe top of the evaporator to an intermediate point ofthe accumulator, said latter connection extending into the interior ofthe accumulator and being downwardly directed, a connection from thecompressor through the condenser and into said latterconnection wherebythe same' conductscondensed refrigerant from the condenser in additionto the vaporized refrigerant from the evaporatorinto the accumulator tofall from the downwardly directed connectained in said vapors, said'mesh screen means comprising at least two oppositely sloping screens,one set'of strands of :each being arranged to 'drain the liquid of theintercepted globules back intothe' bottomof the accumulator.

3. In a refrigeratin systemhaving acompressor, a condenser, anevaporator and an accumulator, a refrigerant vapor flow connection fromthe upper end of the accumulator to the compressor, a series flowconnection between the formerand the evaporator compressing a connectonfor flow of "liquid refrigerant fromthe bottom of theac-cumulator to thebottom ofjthe evaporatorand afcohnection for flow of vaporizedrefrigerant from the top of the evaporator to an intermediate. point ofthe accumulator, said'latter connection extending into the interior ofthe accumulatorabovefthe bottom thereof, a connection from thecompressor through the condenser and-into said latter connection wherebythe same conducts condensed refrigerant from the, condenser in additionto the vaporized'refrigerant fromthe evaporator into the accumulator tofall. into the bottom of the accumulator, and means .in the accumulatorbetween the vaporized refrigerant connection and the connection to thecompressor for unrestrictedly passing refrigerant vapors to thecompressor and for intercepting. and disintegrating globules of liquidrefrigerant contained insaid vapors.

4. In a refrigerating system having a compressor, a condenserfanevaporator and an ac-- .cumulator, a refrigerant vapor fiow connectionfrornthe'upper end of the accumulator to the compressorpa seriesflowconnection between the former and the'levaporator comprising aconnection for a flow of liquid refrigerant 'fromthebot' tom of theaccumulator to the bottom of the evaporator and a connection for flow ofvaporized refrigerant from the top of the evaporator to an intermediatepoint of the accumulator, said latter connection extending into theinterior of the accumulator and being downwardly directed, a

" connection from the compressor through the and for intercepting anddisintegrating globules of liquid refrigerant contained in said vapors.JAMES C. McBROOM.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,280,765 Kramer Oct. 18, 19182,325,657 Burkness Aug. 3, 1943 FOREIGN PATENTS Number Country Date174,633 Germany Oct. 1, 1906

